The City of Philadelphia will release a master plan Thursday for six miles along the lower Schuylkill seen as ripe for job-generating industrial and commercial uses, new roads, more green space, and added bicycle and pedestrian trails.

The blueprint envisions three districts along the river's banks, stretching from University City to Philadelphia International Airport.

"The area accounts for 68 percent of the city's underutilized and vacant industrial land," said Alan Greenberger, deputy mayor for economic development. Refineries, utilities, freight rail lines, scrap yards, and remnants of industries that grew up on the rail lines that passed through the area all call it home.

Greenberger and Philadelphia Industrial Development Corp. (PIDC) president John Grady will present the plan at 10 a.m. Thursday at Bartram's Garden, part of the Fairmount Park system, at 54th Street and Lindbergh Boulevard.

"This is an area that's completely hidden to the public," Grady said. "Part has to do with the types of uses that were here, and part is there was no access into this area. Even if you wanted to go down there, it would be very difficult to find your way around."

The long-range vision of the city's Planning Commission and Commerce Department and PIDC is for targeted public investment in new roads, extending 47th Street over railroad tracks, and creating a new river road on the Schuylkill's west bank.

Development will be focused in three areas:

An "innovation district" around Bartram's Garden for businesses, technology and life-science companies, and research spun out of nearby universities and medical schools. The area would connect with a bicycle and pedestrian river trail north to academic campuses in University City.

An "energy corridor" that includes the former Sunoco oil refinery, owned now by Philadelphia Energy Solutions, geared to traditional energy generation and distribution, Marcellus Shale gas processing, distribution and export, and new energy technologies and facilities, potentially including gas-to-liquids, cogeneration, and trash-to-steam.

A "logistics hub" closer to the airport catering to related businesses, warehousing, airport suppliers and service providers, passenger- and air-freight-related businesses, and manufacturing.

The plan projects $411 million in public infrastructure investment in roads, the environment, and public amenities that would attract more than $860 million in private investment and up to 6,500 new jobs while establishing 46 acres of green space and five miles of new trails.

Among five "early action" projects identified by city planners, the Pennsylvania Department of Transportation is scheduled to make upgrades to the Grays Ferry Bridge in 2015 and 2016 to include bicycle and pedestrian features to better connect the east and west sides of the river while providing an interim link between the Schuylkill River Trail and its planned extension on the west bank.

The University of Pennsylvania is planning for its "South Bank" campus on 23 acres, the former DuPont Co. Marshall Laboratory site at 34th Street and Grays Ferry Avenue. The mixed-use campus aims to nurture start-up businesses and "technology transfer," where faculty with discoveries can bring ideas to market, as well as expanded Penn institutional activity.

PIDC has acquired about 50 acres on either side of Bartram's Garden, and obtained state and federal grants to do brownfield remediation on land once used for oil storage. PIDC is cleaning up the properties before marketing the sites for development.

The Schuylkill River Trail will be extended to the west bank between the Grays Ferry Bridge and 58th Street, and eventually farther south to Fort Mifflin. Design and planning are under way for "Bartram's Mile," a one-mile stretch of new recreation trail next to Bartram's Garden.

Philadelphia Energy Solutions has built a new rail facility at the north end of the refinery that is being used to bring in Bakken oil by train from North Dakota.